Today I am ordering all the studs, nuts, washers, locks and a gasket for my leaking exhaust manifold. i.imgur.com/S5uDDG0.jpg

It only leaks when the machine is first started up, when things heat up, it seals.

I'd rather not have this turn into a boondoggle where I'm removing the head to have a machine shop put in helicoils because I butchered the stud removal.

Any tips on how to R&R the manifold without breaking anything would be greatly appreciated. This has been leaking for a while but I have always been leery of touching it. It looks like I have to remove some injector lines, so I will have to do some fuel system bleeding?

Its a can of worms. I guess you are to the point where you want to open it, but just saying.......

If you are lucky, the manifold will slip off the studs with a little persuasion. Might need to heat the manifold around the studs to get it loose. If you cannot get it off, you might be able to blow the studs out of the hole in the cast iron enough to help some. They could be stainless studs?? If all else fails you, may be able to stick a hacksaw blade up between the manifold and the head and saw the stuck studs off. Once you get the manifold off you can surely press or drive the studs out of the manifold.

This brings you to the point of dealing with getting broken off studs out of the head. Fun! Fun! Fun!

Maybe it will be the exception to the rule and you won't break any studs getting the manifold off and they will be in good shape, so you won't want to replace them and break any off that way.

I got to do the same job on a 466 Deere in a combine last fall. I had one stud broken off to start with and ended up with 3 i think before it was over. On the combine I was really leery of making too many sparks and I didn't think I could blow them out of the blind holes in the head without damaging it and making things worse. Also was away from where I could get a welder to it to try welding on washers and nuts. So I ended up drilling them and attempted using screw extractors which got one. Had to drill and tap the remaining ones.

Good luck! Keep fire control in mind if you get out the torch and welder.

I just have a feeling that once I start, it will end with me having to pull the head, and then I find xyz, and then the machine sits for 10 years.

Well, I'm buying the parts I need to do the job anyways, not sure when I will actually tackle the job.

With that kind of leak I have, will continuing to run the machine as-is cause any damage? Burn up the valves etc?

My opinion.......No problem running it like it is.

My combine was bad.....sounded like it had a rod bearing knocking and being turbocharged it was a little off on power from the leak. The 466 Deere engine is wound up pretty tight in that combine, so no room for much to be wrong before it becomes noticeable. I put up with the leak until it rained and then tore into it.

Keep it running,those studs will break off, you should be able to loosen the nuts a couple of turns and slide the manifold up rear end first and slip it out. That's the easy bit, the studs and nuts are not stainless, they will be corroded, some will come straight out of the head, some will break off, those behind the fuel pump are a swine to get to with a drill. Cat actually supply a jig to bolt on the head as a service tool so you can drill the studs out.
Leave well alone unless it leaks badly.

If you leave it continue as is the carbon and moisture at first start up will erode the head at the gasket sealing surface then you will end up removing head to have the manifold surface areas planed, that is if they dont get pitted too deep.
Gary

"ROME/KG" wrote:

If you leave it continue as is the carbon and moisture at first start up will erode the head at the gasket sealing surface then you will end up removing head to have the manifold surface areas planed, that is if they dont get pitted too deep.
Gary

Yeah, the leaking gasket really should be addressed I think. But I just know the task will snowball.

Hello to all
This is what I do with very good success
First thing is get out my pneumatic hammer (rattle gun)
With a good sharp chisel bit cut the nut or just stretch it somewhat then remove nut. Get manifold off then get a flat jawed vice grip out change bits in my rattle gun to a hammer head style clamp the vice grip on the stud apply pressure and start with the rattle gun straight on the end of the stud not getting crazy with the rattle gun work the vice grip back and forth works for me

Best of luck

"Bmr" wrote:

Hello to all
This is what I do with very good success
First thing is get out my pneumatic hammer (rattle gun)
With a good sharp chisel bit cut the nut or just stretch it somewhat then remove nut. Get manifold off then get a flat jawed vice grip out change bits in my rattle gun to a hammer head style clamp the vice grip on the stud apply pressure and start with the rattle gun straight on the end of the stud not getting crazy with the rattle gun work the vice grip back and forth works for me

Best of luck

That sounds like a decent system!

Are the studs tapered threads into the head?

Thanks for the tip.

My experience is that a Vise-Grip will just chew up the stud.

A 6" pipe wrench used in the same manner will grip much better.